When I arrived at the squadron ready room to plan for my dedicated field work (DFW) flight, I had no reason to believe it would be different from any of the other flights I had conducted. DFWs are fairly common within our community and provide multiple pilots the opportunity to maintain proficiency with respect to approaches and landings. After flight planning, my crew performed preflight the same way we had many times before.

Both I, as the patrol plane commander (PPC), and the senior flight engineer (FE) performed thorough inspections of the aircraft, found no discrepancies and agreed our plane was safe to fly. We started engines and taxied out to the hold short for what we thought would be a nice day of flying in visual conditions. After receiving take off clearance, we began our takeoff roll and shortly after rotating the co-pilot called for the landing gear to be raised. After raising the gear handle, I noted a gear UNSAFE UP indication with the gear handle light remaining illuminated for approximately 45 seconds before finally receiving the expected three UP indication. The FE immediately voiced his concern as it normally takes approximately 10 seconds for the landing gear to fully retract. Suspecting abnormal operation, we opened NATOPS to the functional check flight chapter and verified the limit for landing gear retraction at 150 knots to be between nine and 11.5 seconds.

We started discussing our options and decided that the best course of action was to continue on our clearance and troubleshoot during the transit once at altitude. After we leveled off we began discussing possible causes and referenced NATOPS. There are several landing gear malfunctions that have specific procedures delineating how they are to be handled; however, this was not one of them. In order to determine the reason for the slow retraction and correct it in flight, we were going to have to use our systems knowledge that we had gained throughout our upgrading process.

Our FE recalled that a maintenance action form (MAF) had been signed off for the landing gear star valve and concluded an inspection of the hydraulic service center (HSC) may help in determining the cause of our slow gear retraction. He returned to the flight station and informed us that the landing gear star valve did not appear to be fully open and was also not safety wired (normal state for this valve is safety wired full open in order to allow full hydraulic system pressure to raise and lower the main landing gear). No one recalled noticing this discrepancy during preflight and we began to discuss our options.

We decided to attempt opening the shutoff valve while airborne to prevent any sort of landing gear malfunction when we elected to lower the gear. The FE again went back to the HSC and rotated the valve to what he thought was the full open position. In an effort to determine if our actions corrected the malfunction, we decided to lower the landing gear at altitude.

After approximately 30 seconds, we received a down and locked indication for the nose wheel but the main landing gear displayed an unsafe down condition. These were not the indications we were hoping for! Our FE, realizing he may have closed the landing gear star valve instead of opening it, suggested verifying the position once again. After rotating the star valve to the full opposite position, the main mounts extended and we received a “three down and locked” indication in the flight station.

I immediately felt a sense of relief, and after a lengthy discussion we elected to keep the landing gear down and return to Whidbey Island. The transit home was approximately 80 miles and we completed an uneventful, full stop landing.

Speaking with maintenance control, it was confirmed that previous landing gear system maintenance had not been properly conducted, and as a result the star valve was never safety wired full open as required. During our preflight inspection my FE and I separately examined the hydraulic service center. However, neither of us caught the missing safety wire or recognized that the star valve was not in the full open position. Preflight is our last chance as aircrew to ensure the aircraft is safe for flight, and accomplishing a thorough inspection is paramount to safe operations.

We are fortunate that our flight engineer recalled reading the MAF in the ADB and had the knowledge to troubleshoot and correct our malfunction in flight. It can be argued that several procedures should have prevented this aircraft from being released safe-for-flight; however, that does not provide an excuse for a poorly executed preflight. As the PPC, I take full responsibility and have walked away from this experience with a renewed sense of vigilance when conducting preflights. Hopefully my experience will serve as yet another reminder that aviation remains inherently dangerous, and we cannot allow anything that we do to ever become mundane or routine.

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